In New York City, you would come across a small house, home to a family known as the Littles. You would happen to think of them as the nicest family you'd ever meet. One day, Fredrick and Eleanor, both parents and Littles, ho to and orphanage to find a brother for their son, George. While at it, they meet Stuart, a small, but charming mouse, who apparently, is human-civilized. They adopt him, and everyone, even George, loves him. But there is one problem with Stuart's life, Snowbell, the Little family cat, who wants him. But when trouble starts up almost immediately, Stuart must make it back to his home-before snowbell's friends find out about him
